Current status and issues of flexible devices for thermoelectric conversion

Abstract

Thermoelectric conversion that produces electromotive force from temperature differences in materials is being re-recognized as an “old and new” energy harvesting technique due to the rapid development of Internet of Things (IoT) technology. In particular, flexible thermoelectric devices that use the human body as a heat source are currently regarded as promising power generators that support wearable electronics, although the thermoelectric effect of flexible and large-area polycrystalline thin films that are suitable for wearable applications has not been well explored. In this tutorial, we review the current status and future prospects for thermoelectric research of polycrystalline thin films, which have shown remarkable progress in recent years, based mainly on our recent study.